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Vitamin C and the Limeys : Sal and Dr. David Agus talk about the history of Scurvy and Vitamin C
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- Sal: I am here with Dr. Agus who is a professor of Medicine and Engineering at the University of Southern California and what are we looking at right over here?
- Dr Agus: You can see on the right top there is the Captain of the British Royal Navy named James Lind and he was a remarkable guy, actually he did one of the first clinical trials and I will tell you about him in a minute.
- But in the Battle of Trafalgar between the British and the French he did something very clever, in that on his ships he had fresh fruit- he had limes, hence the term Lyme for the British soldiers.
- What was amazing is that being out at sea for several weeks at a time, the soldiers would all start to
- develop scurvy, which is a lack of vitamin C.
- Sal: What happens to someone when they have scurvy?
- Dr Agus: So the vitamin C is involved in collagen synthesis which is kind of the scaffolding of the body
- and so your body starts to degrade, you start to get bleeding gums, your tissues start to fall apart.
- And it ends up in death in most people if no vitamin C is given.
- Sal: I see, all your connective tissue in your body starts to degrade
- Dr Agus: Literally starts to degrade.
- Sal: And it can't rebuild itself. Wow.
- Dr. Agus: So in the late 90's I was working in a laboratory and I read his book, it's called "A Treatus Called Scurvy from 1746."
- And in it, he said that, uh uh, talked all about doing autopsies on people with scurvy.
- People my age, and I'm in my 40s have never seen scurvy, ever. So the first time I ever heard about scurvy and what it looked like was reading it.
- And what he mentioned was that the brain was always intact in people with scurvy.
- So when I looked to identify how vitamin C worked in the body, what the transporter was, the first place
- I looked was the brain.
- And science, it kind of overlooked looking there for this transporter because no one had read the book
- in a long time. We cloned, which is identified the gene to allow vitamin C to go in and out of cells.
- It's a pretty cool molecule because the Vitamin C that you eat is called ascorbic acid,
- and in order to get it into cells, it has to be converted into another molecule called dehydroascorbic acid.
- But what's amazing is, is that in the medical textbooks, as late as the 1920's
- and 30's, they still called scurvy an infectious disease.
- Because at the end of his book he put a paragraph where he said "I happen to sell the extract
- of lime to prevent scurvy and it didn't work." And it didn't work because as soon as you squeeze
- that lime at room temperature the vitamin C degrades.
- And so, people tried to reproduce what he did and they couldn't.
- And you know, he was an entrepreneur, he couldn't sell limes, cause everybody had limes,
- so he tried to sell the extract of limes and it didn't work.
- Sal: So even though he was able to, the clinical trial that he ran, was regarding limes
- and scurvy.
- Dr. Agus: Yes, he took these nuns and he gave them a diet that had
- no fruits in it and then a diet with limes.
- And he showed that the people who had the limes didn't develop scurvy
- and others died.
- Sal: So he just watched some nuns have, get scurvy and die.
- Dr Agus: Not the most ethical experiment in the world.
- Sal: No, no, yes. So he's not necessarily the most, the most...
- Dr Agus: But, he did that in the 1740s and that was
- Sal: ...ethical person in the world. But but, he he learned, that oh the limes will at least, it seemed, prevent scurvy.
- Dr. Agus: Right. Remember, what a vitamin is, and this is key,
- What a vitamin is is something the body can't synthesize enough of.
- So for example, a mouse has an enzyme that allows it to synthesize vitamin C
- So in a mouse, it wouldn't be called vitamin C, it would just be called ascorbic acid.
- Cause it's not really a vitamin.
- Sal: Interesting, interesting. So if we were mouse doctors,
- we would just call it, we would just call it ascorbic acid.
- Dr. Agus: Exactly. If we were mice, we'd call it ascorbic acid too!
- Sal: Exactly!
- Dr Agus: Um, or they probably have their own language.
- Sal: Right, right.
- Dr Agus: But, in all of us, we have certain things that we have to get from the outside from
- food and those are called vitamins and minerals.
- So a vitamin doesn't mean that more is better. Doesn't mean that it's good for you.
- It just means that you require a small amount of it and your body can't synthesize it.
- Sal: So this guy right here, he does a clinical trial with the nuns,
- he figures out that lime, people who have fruit, who have lime are not getting
- scurvy, and so he sends out a bunch of lime with the British, the Navy during the
- Napoleonic wars, and that's why they're called Lymes.
- And, I guess apparently, they won the war because of that.
- Because once you're at war you're several weeks at sea,
- the French navy is getting decimated with scurvy. Because they're not getting,
- they're eating dry, they're eating beef jerky or whatever else they might be eating.
- They're not getting fruit. So it's really, it's because of that of that
- discovery, because of that discovery, the British won the battle of Trafalgar.
- Dr Agus: Exactly. Two lessons from it.
- One is, you know, you can't just say generically lime,
- you matter how the fruit is, how it's cared for.
- You know, once he juiced it and put it at room temperature, it was all gone.
- Sal: Right, so besides the fact that this guy did a clinical trial that killed a bunch of nuns,
- he also said 'Hey, this is a business opportunity"
- Dr Agus: Right
- Sal: I've just shown, maybe he felt that he didn't get compensated properly for saving the British
- Fleet from Napoleon and says "I'm going to make a business out of this."
- And so he decides to start taking lime juice extract and tries to sell it
- as a cure for, what happened, why didn't he become rich?
- Dr Agus: Because it didn't work.
- Once you squeeze it out of the lime, it degrades the vitamin C.
- Literally it's called 'oxidizes'. And it happens when it's
- been exposed to light and oxygen in room temperature. Almost instantaneously!
- Sal: I see. So what happened was, when the soldiers were eating the lime in the whole form,
- sure you may chew on it a little bit, you might cut it a little bit, but there's
- whole peices of lime that were not exposed, where the vitamin C wasn't exposed to the air
- or whatever else, that actually got into someones system.
- Dr Agus: Exactly. There's a reason Tropicana, when they sell you
- orange juice, it's in a cardboard container that gets no light in and it's refrigerated.
- Because that keeps the vitamin C intact.
- Sal: Right. So because people didn't realize that, because they said, hey ok, for whatever reason
- they didn't get scurvy during Traflagar
- but, hey we have the lime extract and
- that's not preventing scurvy, people kind of gave up on that whole hypothesis.
- That it was about the vitamin C. And that's why you're saying, as
- recent as the 1920's people
- thought it was about, some type of infectious disease.
- Dr. Agus: Exactly.
- So, the key is when you start to look at data, you have to look at all aspects of it.
- And somebody smart should have looked and said,
- 'Listen, how he did his first experiment was different than what he was selling and trying to validate"
- Sal: That's interesting.
- Dr Agus: If someone had looked at that for 200 years, we would have saved a lot of lives.
- Because remember, it was from 1946 til the 1930's that we discovered what vitamin C
- truly was.
- And so a lot of lives were lost then because nobody paid attention
- Sal: Fascinating. There's these other side affects of, one a vitamin doesn't necessarily mean a good thing.
- That's something kind of programmed into us,
- maybe by the nutracutical industry.
- But, but, even if it is a good thing, it's not even necessarily a good thing to get it
- in a processed form. And this isn't some type of, you know, some tree-hugging organic,
- there's some science here that's like look, if something is an antioxidant
- and it gets exposed to oxygen or some other oxydizing agent,
- it's not going to be able to do any good any more.
- Dr Agus: It's chemistry. Yeah.
- Sal: So that's where the whole, the actual fruit is going to be more valued.
- Dr. Agus: And remember, one orange has a couple of milligrams of vitamin C
- One, two, three milligrams.
- One pill has 500 milligrams.
- Sal: Right.
- Dr Agus: So whoever is making those pills kind of forgot what was going on in nature.
- Sal: Right. Right, fascinating. This is very good.
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